Since its discovery, dioxirane has found many uses including epoxification reactions, disinfection, decontamination, laundry bleaching, and the like. It has also been reported that carbonyl chemistry from both ketone and aldehyde donors are suitable for the generation of dioxiranes. Dioxiranes can be produced through decomposition of potassium monopersulfate. Accelerated decomposition of potassium monopersulfate ion (KHSO5−) was reported by Montgomery, R. E. J. Am. Chem. Soc. 1974, 96, 7820. Montgomery observed and reported that ketone (acetone) can catalyze the decomposition of Oxone® (a triple salt of potassium peroxymonosulfate) to form dimethyldioxirane (DMD).
A simplified method of producing dimethyldioxirane (DMD) was presented by Adam, W.; Bialas, J.; Hadjiarapoglou, L. Chem. Ber. 1991, 124, 2377. This process required rigorously controlled temperature <15° C., sodium hydrogen carbonate, potassium peroxymonosulfate, and rigorous stirring produces a 0.09-0.1 M acetone solution of dimethyldioxirane.
Ferrer, M.; Gibert, M.; Sanchez-Baeza, F.; Messeguer, A. Tetrahedron Lett. 1996, 37, 3585. disclosed a method resulting in yet higher yields (0.4 M) dimethyldioxirane solution have been developed requiring chlorinate solvents such as CHCl3 or CCl4. Use of such solvent is limited to laboratory applications.
Mello, R.; Fiorentino, M.; Sciacovelli, O.; Curci, R. J. Org. Chem. 1988, 53, 3890. Mello, reported a method of producing methyl(trifluoromethyl)dioxirane from 1,1,1,trifluoropropanone.
However, although dioxiranes have numerous potential applications, their use has been limited in utility because of the high cost associated with their production. Thus, dioxiranes have been used mainly in organic synthesis and applications where a high expense associated with poor yields and/or laborious reaction conditions can be justified.
One way to expand the application of dioxiranes is to replace exotic and expensive carbonyl donors with readily available (e.g., commercially produced) carbonyl sources. Dioxirane application can be further expanded by expediting the in-situ generation of dioxiranes to provide effective dioxirane yields within minutes from the initiation of the reaction. An expedited time period would be, e.g., within 30 minutes, and more preferably within 5 minutes. It is also desirable to induce the reaction under a wide range of operational conditions such as pH, concentration of reactants, and temperature.
Unfortunately, most of the commercially available ketones and aldehydes that can be cost-effectively purchased and applied are slow-reacting, and as a result require hours of reaction time to produce desirable yields. Table 1 below compares the rate of peroxymonosulfate decomposition for various ketones:
TABLE 1Relative Rate of Peroxymonosulfate DecompositionKetoneRelative RateNone1Acetone10Cyclohexanone94Oxopiperidinium14,000
U.S. Pat. No. 5,785,887 discloses the use of a peroxygen ketalcycloalkanedione bleachant activator.
WO09923294A1 discloses a 2-step process whereby the second step includes producing an acidic dioxirane solution from potassium peroxymonosulfate and preferably oxopiperidinium salts.
U.S. Application 2005/0085402 discloses a solution containing dioxirane for purposes of decontamination.
U.S. Applications 2005/0192195, 2005/018726, 2004/0048763, and 2004/0038843, disclose a catalytic system and methods of oxidizing materials using the invention containing a metal catalyst complexed with selected macropolycyclic rigid ligands. This invention can be used with many conventional bleaching agents and bleach activators such as peroxycarboxylic acids to enhance oxidation of materials.